A Park police officer walks through the wreckage from a medical helicopter that crashed Saturday at Walter Mill Regional Park in Md. Monday. The medical helicopter was carrying victims of a weekend traffic accident when it went down in a suburban Washington park late Saturday night. (AP Photo/Jose Luis Magana)

By Brian Westley and Nafeesa Syeed The Associated Press

DISTRICT HEIGHTS, Md. — The decision had been made safely many times before: Victims in a car crash were critically injured, and a helicopter was dispatched to rush them to the hospital.

But before the emergency team ever got the patients to waiting doctors, the pilot struggled in the darkness and fog. Soon, he radioed that conditions were difficult, and said he would land elsewhere. The radio eventually went silent - and the helicopter was discovered in a crumpled heap on a woodsy hillside, with four of its five occupants dead.

The weekend's crash at a park in suburban Washington, D.C., was the eighth fatal crash in the past 12 months across the country involving medical transport helicopters. Observers say the accident demonstrates a disturbing rise in the number of emergency air transport crashes, and wonder if a system designed to save lives may be costing them.

Aviation authorities also are signaling that it may be time to discuss regulatory changes, and planning a public hearing to analyze what's causing the increase in crashes. They also could discuss how decisions are made when officials choose to transport patients by air or by ground.

Dr. Bryan Bledsoe, an emergency medicine physician who teaches at the University of Nevada and has researched accident rates of medical helicopters, said the Maryland medevac system has a good safety record, but medical flights are sometimes too favored over old-fashioned ambulances.

"We vastly overuse them, patients don't benefit and they are expensive," he said.

Maryland emergency officials haven't described in detail what influenced their decision to launch a helicopter before Saturday's crash, saying only they were following state emergency procedures and that they considered the severity of the victims' injuries. They also have said when the helicopter initially took off, there was seven miles of visibility. By the time of the crash, however, conditions had deteriorated to the point that the pilot had to rely on instruments to help him land.

Dawn Mancuso, the executive director of the Association of Air Medical Services, said time, distance and other factors can influence when to use a helicopter over an ambulance in an emergency. The split-second decision can be complicated by the fact that the ones making the call don't have access to an ultrasound or CAT scan - and have to err on the side of getting a patient to a hospital faster.

"It's easy to second-guess what happens once the patient's been cared for," Mancuso said. Medical providers "are making their best educated guess to what the needs of the patient are - and sometimes they're wrong."

In the last 12 months, 31 people have been killed in accidents involving medical helicopters, the National Transportation Safety Board said. A federal investigation in 2006 found there were 55 air ambulance accidents nationally from 2002 to 2005, resulting in 54 fatalities.

Federal Aviation Administration spokeswoman Alison Duquette said the agency is concerned, and is working with EMS associations to figure out what more they can do to reduce accidents.

The state-run helicopter program in Maryland had been known for its safety record, with just three other fatal crashes in four decades. But in recent weeks, concerns had been raised about the fleet's age and maintenance.

Last week, two state senators wrote to the FAA saying that Maryland's helicopters "are aging and represent a considerable degree of complexity in terms of maintenance and repair capabilities." The helicopter that crashed was the second-oldest in the state's fleet, though it had passed an inspection only days before the flight.

The helicopter did not have a terrain awareness warning system that would have alerted the pilot he was flying dangerously close to trees, said National Transportation Safety Board member Debbie Hersman. The NTSB in 2006 recommended that emergency medical helicopters begin using the equipment.

State Police have temporarily grounded medical flights as investigators work to determine a cause. Dr. Robert Bass, director of the Maryland Institute for Emergency Medical Services Systems, said he's hopeful some helicopters can go back into use in the next two or three days, but no one is rushing to reinstate the flights.

"We're not pushing them," Bass said. "We want them to be safe, and so we're just waiting to hear from them about when they're comfortable in putting the helocopters back on line."

The lone survivor of the crash was in critical but stable condition in a hospital Monday. Eighteen-year-old Jordan Wells' father, Scott, said his daughter spent an extended amount of time in the woods after the crash waiting for help. She is unable to speak, but she can squeeze doctors' hands, he said.

"We have a mix of emotions," he said. "...We do believe God saved Jordan and we're just waiting to find out why."

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